Répartition de l'uranium et du thorium dans les apatites : implications pour la thermochronologie UTh/He
Bibliographic record
Abstract
La technique de thermochronologie par UTh/He suppose une répartition homogène de l'uranium et du thorium dans les minéraux analysés. L'utilisation de la cathodoluminescence permet de mettre en évidence une forte hétérogénéité chimique dans les apatites, minéral couramment utilisé pour cette méthode de datation. Cette hétérogénéité est alors susceptible d'entraı̂ner des erreurs dans le calcul de l'âge UTh/He. L'analyse chimique par ICP–MS à ablation laser des différentes zones repérées en cathodoluminescence permet de faire le lien entre les variations de concentration en Ce, U, Th et l'intensité de la luminescence, et rend possible la correction de l'âge UTh/He.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".